a. Field of the Invention
The invention relates generally to electronic image displays and illumination devices, and to means for making same.
b. Prior Art
Previous light-emitting, electronic image displays have been of a wide variety of different technologies, with each suited to a limited range of uses, and no single system being suitable for most or all applications. Most light-emitting display technologies have not been bright enough to be used in full sunlight. Further, the most widely used display, the cathode ray tube, is limited to a relatively small screen size, while demand is growing for larger television displays. The CRT has the additional disadvantage of requiring a depth behind the screen approximately equal to the vertical dimension of the screen, which results in a very large, bulky, heavy system. The CRT consists of an evacuated tube with phosphor coated faceplate, which emits light when struck by a cathode ray emitted from the back of the tube. The ray scans the screen surface rapidly, creating an image in full color, and with lifelike motion. Recent CRT systems have projected the image onto an enlarged remote screen.
Other light-emitting display technologies include electroluminescent flat panels of luminescent materials which are caused to glow by application of voltage to the luminescent material. To date, brightness is too low to satisfy the marketplace.
AC gas plasma display is a flat panel envelope filled with a gas which breaks down at electrode crosspoints, causing emission of a reddish orange light.
Incandescent display panels such as U.S. Pat. Nos. 3,715,785 and 3,846,661 have demonstrated that incandescent technology has many advantages, but failed to demonstrate a truly economical, commercially practical system with televisionlike resolution. The inventors did demonstrate that an incandescent display with a great plurality of pixels can be mass produced, and is economical to operate. The present disclosure, however, teaches that filaments have disadvantages in flat panel displays, and overcomes them.
In U.S. Pat. Nos. 454,622 and 514,170 in 1891 and 1894, Tesla demonstrated a non-filament, carbon button incandescent light element wherein incandescence is caused by molecular bombardment rather than by joule heating. The button is twenty times more efficient a light producer than today's incandescent filaments, but is not used commercially due to the impractically high voltages and frequencies required to drive it.
A major object of the present invention was to devise a practical, bright, high resolution, flat panel display capable of being constructed to any dimensions and shape, and which is versatile enough to meet the needs of an almost universal range of applications.
Another major object was to devise a flat panel television/display capable of being built to any size, bright enough to be viewed in full sunlight, and with resolution potential exceeding that of high fidelity projected film images.
Yet another major object was to devise a flat panel display durable enough and bright enough for military applications.
An object of the invention was to devise an image display panel small enough to be easily portable, as for portable televisions and dynabooks.
Another object was to devise a vehicular display panel, durable and bright enough for use in vehicle instrument panels.
Yet another object was to devise a high resolution display to show computer generated data, as a computer peripheral device.
Still another object was to devise a display panel for a wide variety of office machines, such as word processors, which would have superior optical properties, be attractive to look at, and would not emit harmful radiation or be overly tiring to view for extended periods.
A further object was to devise a display suitable for creating a heads-up display system in the likes of military aircraft, commercial airliners, and automobiles.
Yet a further object was to devise bright, easily readable, electronically alterable signs or message panels.
Still a further object was to devise a lighting system suitable for thin automobile tail lamp panels.
Yet still another object was to devise a versatile flat panel architectural lighting system.
Another further object was to devise a completely transparent display panel for such uses as a map overlay.
Still another further object was to devise a display capable of displaying three dimensional images.
Yet another further object was to devise a light source for important uses such as traffic lights, which could not fail or burn out suddenly.
And yet another further object was to devise an incandescent light element which would be a point source of light, and which could be driven rapidly enough to display television-like moving images.
And still another further object was to devise a non-mechanical means to mass produce a display panel comprised of a great plurality of incandescent points of light.
And yet still another further object was to devise a display panel which operates on approximately five volts, to be compatible with standard solid-state circuitry, and use the same power supply provided therefor.